This invention relates to an instrument for removing tissue from a bone to create a cavity.
The acetabular component of common hip joint prostheses comprises a part-spherical shell which can be implanted in the patient's acetabulum. Generally the shell is formed from a metallic material. A liner component is fitted to the shell. The liner component is formed from a polymeric material such as an ultrahigh molecular weight polyethylene (UHMWPE) and provides the bearing surface for articulation with the convex head of a femoral component.
U.S. Pat. No. 2,910,978 discloses an acetabular component which has a notch formed in it. The notch has a rounded portion towards the pole of the component, and a narrower neck portion which extends from the rounded portion to the peripheral edge of the component. The notch allows fat pad tissue in the acetabular fossa to be preserved when the acetabulum is prepared to receive the prosthesis component. This can promote lubrication of the joint during articulation.